The present invention relates to an improvement for a circular walker, and particularly to an improvement of the seat structure and improvement of the wheels, and such improvement is a novel structure to make easy and quick manufacture, assembly and disassembly. The structure of such wheels may prevent foreign goods from rolling into the axle center without need of rivetting the axle center so that it may attain such effects as easy and quick manufacture to reduce the production cost and minimize the risk of the wheel failure due to the influence of foreign goods.
The structure of conventional circular walker as shown in FIGS. 1A and 1B, and referring to FIG. 1A, it adopts buckle type assembly, and referring to FIG. 1B, it adopts screw type assembly. Referring to FIG. 1A, buckle type comprises a plurality of male buckles 21 distributed around the perimeter of assembly edge between the seat 11 and backrest 12, corresponding to the female buckles 22 on the binding 13, and for the assembly of the carriage, put the binding 13 on the carriage and press fit of male and female buckles 21, 22; referring to FIG. B, the seat is connected to the backrest 31, and a plurality of bolts 32 are set on the bottom edge of the backrest 31 and assembled on the top bowl 34 of the carriage, and a plurality of wing nuts 33 to screw up from the bottom of the top bowl 34.
The assembly of the two seats has the following defects:
1. Though buckle type is easy and quick for assembly, however, during the production the split sewing of male and females buckles must be properly align and this will cause additional trouble to the sewing workers so that sewing speed will become very slow.
2. Buckle type engaging strength is relatively weak to sustain less tension, and for a baby learning walking, it is very easy for it to suffer unexpected injury due to the separation of the seats owing to the buckles forcibly disengaged during the baby is playing by standing or sitting.
3. Screw type assembly: at first stick or screw up the backrest and the seat, then assemble the seat on the top bowl of carriage by means of bolts and wing nuts; not only the assembly procedure is complicated but also wing nuts have to be removed so as to dismount the seat (backrest) for cleanup and random placement of the wing nuts might be dismissed to cause trouble to the user.
4. Screw type assembly: the bolt portion could easily get rusty to cause dismounting problem in the future.
The wheels of the conventional circular walker relates to a simple wheel structure and too simple structure has resulted in durability problem. Referring to FIG. 2, the conventional structure comprises a seat body 1, two wheels 3 and axle rod 5 wherein the axle rod 5 penetrates through the seat body 1, the axle hole 2 of the wheel body 3 and rivetting on the other end (or screwing up by nut), i.e. two wheel bodies 3 have an open slot port 4 for manual rivetting (FIG. 3); it can known the said structure has following defects:
(1) The axle rod 5 (axle center) must be matched the tool for rivetting to increase equipment, assembly trouble and time waste and therefore assembly is not easy to cause higher production cost.
(2) The open slot port 4 on the axle hole 2 of the wheel body 3 is easy to roll in foreign goods such as hair A, thread and fiber, etc. because it is not sealed to cause choking up between the axle rod 5 and axle hole 2 to interfere rotation.
(3) The stress of rotation is sustained by the contact portion between the axle rod 5 and axle hole 2 to cause wearing of axle hole 2 wall to expand axle hole diameter so that rotation is not good due to inferior match with the axle rod 5.
These and other objects and advantages of the present invention will become apparent to those skilled in art after considering the following detailed specification together with the accompanying drawings.